Apparatus and method for measuring cured state of reaction curable resin

ABSTRACT

Ultraviolet light having wavelengths of 250 to 380 nm is irradiated to a reaction curable resin. A screen image of luminance value is recorded which is obtained by extracting only a specific wavelength component of the reflected ultraviolet light, and the cured state of an ultraviolet curable resin is quantified from a captured image and displayed. At the same time, the spectral characteristic of reflected light is measured by an ultraviolet spectroscope and a cured state is quantified in accordance with the change rate of absorbances obtained from a change of spectral characteristics by combining the spectral characteristic with a luminance value image and displayed. Thereby, decrease in defects due to irregular curing and uncured portion of the ultraviolet curable resin can be realized by measuring the temporal change of the cured state of the reaction curable resin as a screen image and optimizing an optimum curing condition of the ultraviolet curable resin.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus and a method for measuringa cured state of a reaction curable resin which changes from liquid tosolid by causing a chemical reaction by stimuli of light and heat.Particularly, the present invention relates to measurement of temporalchange in the cured state.

2. Related Background Art

A reaction curable resin has been frequently used so far in fields ofink, paint, plastic-material coating and lens (glass lens).Particularly, it is known that a replica forming method using anultraviolet curable resin is suitable for a process of forming anoptical device having a minute shape such as a diffractive opticaldevice.

Replica formation is to form an optical device by dripping anultraviolet curable resin on the lens surface previously polished toform the resin into an aspherical shape by a mold and then applyingultraviolet radiation to cure a resultant aspherical layer, andreleasing the molded item from the mold. However, in the case of thereplica forming method, a problem is a defective appearance due to thefluctuation in the cured state of an ultraviolet curable resin.Moreover, because curing excessively advances and thereby the fragilityof the resin is increased, there is also a problem that the opticaldevice is chipped when releasing the optical device from the mold or theshape of the optical device does not become a desired shape because ofreleasing the optical device in an insufficient cured state. Therefore,deriving an optimum curing condition becomes very important by analyzingthe cured state of the ultraviolet curable resin and specifying a factorcausing the problem.

As a method for analyzing and measuring a cured state of a reactioncurable resin, the spectrometry using an infrared light such as FT-IR(Fourier transformation infrared spectral analysis) is general which isdisclosed in Japanese Patent Application Laid-Open No. H06-294734. Formeasuring of the cured state of a resin using FT-IR, it is known thatany one of a photo-curing resin, heat curing resin and two-componentsystem resin can be used. Moreover, to capture the cured state of anultraviolet curable resin as a temporal change, a method for using aninfrared spectrum peak is disclosed in Japanese Patent ApplicationLaid-Open No. 2000-055806. The infrared spectrum peak detects a changeof molecular structures following the curing reaction of an ultravioletcurable resin and measures a change amount of peak intensities accordingto curing.

When generally curing a reaction curable resin, the whole resin is notuniformly cured but a distribution necessarily occurs in curing ratesand irregularity occurs in cured states. As factors to cause adistribution to occur in curing rates, the following are listed: theposition or angle to a light source or heat source differs according toeach portion of a resin, a difference occurs in anaerobiccharacteristics of a resin due to a difference in shape of the resin andthereby the curing reaction rate differs according to each portion ofthe surface of the resin, and the curing reaction rate in the interiorof a resin differs according to a difference in the thickness of eachportion of a resin. Therefore, a measuring method capable of measuring achange of cured states of the resin as a whole following the passage oftime and displaying the change as a screen image is necessary.

However the method using infrared spectroscopic analysis shown inJapanese Patent Application Laid-Open No. H06-294734 and the methodusing an infrared spectrum peak disclosed in Japanese Patent ApplicationLaid-Open No. 2000-055806 are methods for respectively measuring thecured state of a desired one point on an object to be measured. Thus, itis impossible to capture the cured state of a reaction curable resin asa screen image of the whole resin. In the case of these measuringmethods using infrared light, the heat due to infrared light ispropagated to a reaction curable resin. Therefore, in the case of athermal curing resin whose curing reaction progresses due to heat, thereis a problem that the curing reaction of the resin is influenced by theheat and an accurate reaction state cannot be measured. Moreover, whenmeasuring an optical device produced by the replica forming method, areaction curable resin is cured while it is held between a lens and amold. Therefore, to measure the cured state of the reaction curableresin, it is necessary to measure the cured state through the lens.However, it is impossible to measure the cured state because infraredlight does not pass through the glass materials or plastic materialswhich are used as the lens material.

SUMMARY OF THE INVENTION

It is an object of the present invention to make it possible to capturethe cured state of a reaction curable resin as a screen image having acertain area, measure a cured state following passage of time andevaluate and analyze the cured state as a quantitative value. Moreover,it is another object of the present invention to provide a cured-statemeasuring method and an apparatus capable of accurately measuring acured state without generating the heat affecting the curing during themeasurement, even in the space surrounded by the glass or the like.

To solve the above problems, the present invention provides areaction-curable-resin cured-state measuring apparatus including anultraviolet light source for irradiating ultraviolet light to a reactioncurable resin serving as an object to be measured, detection means fordetecting ultraviolet light reflected from or transmitted through thereaction curable resin as screen image data having a certain area andimage processing means for arithmetic-processing the screen image datadetected by the detection means and quantifying the progress state of acuring reaction of the reaction curable resin following the passage oftime as a screen image.

Moreover, the present invention provides a reaction-curable-resincured-state measuring apparatus including an ultraviolet light sourcefor irradiating ultraviolet light to a reaction curable resin serving asan object to be measured, a half mirror for branching the ultravioletlight reflected from or transmitted through the reaction curable resinin two directions, detection means for detecting one-hand ultravioletlight branched by the half mirror as screen image data having a certainarea, an ultraviolet spectroscope for detecting the spectralcharacteristic at one specific point of the other-hand ultraviolet lightbranched of the half mirror and image processing means forarithmetic-processing the screen image data detected by the detectionmeans and the spectral characteristic detected by the ultravioletspectroscope and quantifying the progress state of the curing reactionof the reaction curable resin following the passage of time as a screenimage.

Furthermore, the present invention provides a reaction-curable-resincured-state measuring method including a step of irradiating ultravioletlight to a reaction curable resin serving as an object to be measured, astep of detecting ultraviolet light reflected from or transmittedthrough the reaction curable resin as screen image data having a certainarea, a step of arithmetic-processing the detected screen image data anda step of quantifying the progress state of a curing reaction of thereaction curable resin following the passage of time as a screen image.

Furthermore, the present invention provides a reaction-curable-resincured-state measuring method in which the screen image data is detectedby extracting only a light having a specific wavelength of reflected ortransmitted ultraviolet light.

Furthermore, the present invention provides a reaction-curable-resincured-state measuring method in which the screen image data is theluminance value of the reflected or transmitted ultraviolet light in atleast one wavelength of wavelengths of 250 to 380 nm and the wavelengthis a wavelength at which a change of luminance values following curingof the reaction curable resin appears as the largest value.

Furthermore, the present invention provides a reaction-curable-resincured-state measuring method in which the quantified screen image isdisplayed by setting the change rate of the luminance values to 0%before the curing reaction and to 100% after the curing reaction andthereby displaying the change rate corresponding to the luminance valuesand changing colors at a plurality of gradations.

Furthermore, the present invention provides a reaction-curable-resincured-state measuring method including a step of irradiating ultravioletlight to a reaction curable resin serving as an object to be measured, astep of branching ultraviolet light reflected or transmitted from thereaction curable resin in two directions, a step of detecting branchedone-hand ultraviolet light as screen image data having a certain area, astep of detecting the spectral characteristic of the other branchedultraviolet light at one specific point, and a step ofarithmetic-processing the detected screen image data and spectralcharacteristic and quantifying the progress state of a curing reactionof the reaction curable resin following the passage of time as a screenimage.

Furthermore, the present invention provides a reaction-curable-resincured-state measuring method in which the screen image data is aluminance value of the reflected or transmitted ultraviolet light at atleast one wavelength of wavelengths of 250 to 380 nm and the wavelengthis a wavelength at which a change of luminance values following curingof the reaction curable resin appears as the largest value.

Furthermore, the present invention provides a reaction-curable-resincured-state measuring method in which the quantified screen image isdisplayed by converting the luminance value into an absorbance obtainedfrom the spectral characteristic, setting the change rate of theabsorbance to 0% before the curing reaction and to 100% after the curingreaction, and displaying the change rate of the absorbance changingcolors at a plurality of gradations.

Furthermore, the present invention provides a reaction-curable-resincured-state measuring method in which the reaction curable resin is anultraviolet curable resin.

Furthermore, the present invention provides a reaction-curable-resincured-state measuring method in which the reaction curable resin is anultraviolet curable resin for forming an optical device to be formedthrough replica molding.

The above and other objects of the Invention will become more apparentfrom the following description taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a resin-cured-state measuring apparatus ofembodiment 1;

FIGS. 2A, 2B, 2C and 2D are images obtained by measuring cured states ofthe resin in the embodiment 1;

FIG. 3 is an illustration of graphs showing the states of absorbanceschange following ultraviolet irradiation, of ultraviolet curable resinC001;

FIG. 4 is an illustration of a graph showing the state of an absorbancechange at a wavelength of 300 nm following ultraviolet irradiation, ofthe ultraviolet curable resin C001;

FIG. 5 is an illustration of graphs showing a reaction rate 1 calculatedfrom the infrared spectrum of the ultraviolet curable resin C001 and areaction rate 2 calculated from the change rate of the image luminancevalue of the ultraviolet curable resin;

FIG. 6 is a schematic view of a resin-cured-state measuring apparatus ofembodiment 2;

FIG. 7 is an illustration of a graph showing the spectrum of anultraviolet light source for measurement;

FIGS. 8A, 8B, 8C and 8D are images obtained by measuring cured states ofthe resin in embodiment 2;

FIG. 9 is a schematic view of a resin-cured-state measuring apparatus ofembodiment 3;

FIG. 10 is a schematic view of a resin-cured-state measuring apparatusin embodiment 4;

FIG. 11 is a sectional view of a diffractive optical device to bemeasured in embodiment 5;

FIG. 12 is an image obtained by measuring a resin-cured-state in theembodiment 5;

FIGS. 13A, 13B, 13C, 13D and 13E are schematic views showing the replicaforming process of a diffractive optical device in the embodiment 5;

FIG. 14 is a schematic view of a compact-camera module in embodiment 6;

FIG. 15 is an image obtained by measuring a resin-cured-state in theembodiment 7; and

FIG. 16 is an illustration of graphs showing the states of absorbanceschange in annealing, of ultraviolet curable resin C001 in the embodiment7.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Then, embodiments of the present invention are described below byreferring to the accompanying drawings.

Embodiment 1

FIG. 1 is a schematic view showing the reaction-curable-resincured-state measuring apparatus of the embodiment 1 of the presentinvention. In this case, an ultraviolet curable resin is used as areaction curable resin. This embodiment quantifies and displays thecured state of an ultraviolet curable resin by irradiating ultravioletlight to the ultraviolet curable resin and measuring the reflectedlight.

In FIG. 1, reference numeral 9 denotes an object to be measured(measuring object) made of an ultraviolet curable resin. Referencenumeral 1 denotes an ultraviolet light source. Reference numeral 2 adenotes a half mirror for branching the ultraviolet light emitted fromthe ultraviolet light source 1 in two directions. Reference numeral 3denotes a band-pass filter for passing only a specific wavelengthcomponent of ultraviolet light. Reference numeral 4 denotes anultraviolet lens capable of condensing ultraviolet light and referencenumeral 5 denotes an ultraviolet CCD camera for picking up as a screenimage ultraviolet light reflected from a measuring object and condensedby the ultraviolet lens 4. By changing specifications of the ultravioletCCD camera 5 and the band-pass filter 3, it is possible to change thewavelength of the ultraviolet light to be measured to an optimum valuefor showing a change of cured states in the best state. Referencenumeral 7 denotes an image processing apparatus for storing theluminance value of a measuring object made of an ultraviolet curableresin, converting the luminance value into a cured state and displayingthe cured state. The image processing apparatus 7 quantifies the curedstate of the measuring object 9 from a change of luminance valuesobtained from the ultraviolet CCD camera 5 and displays the cured state.Reference numeral 8 denotes a stray-light removal plate to shieldunnecessary ultraviolet light.

In the case of acrylic resins and epoxy resins widely used asultraviolet curable resins, the intensity of ultraviolet light to betransmitted gradually becomes weak as curing progresses in anultraviolet wavelength band. That is, the luminance value of the lightreflected from an ultraviolet curable resin is changed in accordancewith progress of the curing reaction of the ultraviolet curable resin.This embodiment quantifies a cured state from a change of luminancevalues of the light reflected from an ultraviolet curable resin anddisplays the cured state.

The ultraviolet light (wavelengths of 250 to 380 nm) emitted from theultraviolet light source 1 is first divided into two directions such asdirect advance and reflection by a half mirror 2 a. The direct-advanceultraviolet light is shielded by the stray-light removal plate 8. Theultraviolet light reflected from the half mirror 2 a is irradiated to anultraviolet curable resin serving as an object to be measured. Thecuring reaction of the ultraviolet curable resin is slowly progressed bythe ultraviolet light. Only a specific wavelength component is extractedfrom the ultraviolet light reflected from the ultraviolet curable resinby the band-pass filter 3 and picked up as a screen image by theultraviolet CCD camera 5. The image picked up by the ultraviolet CCDcamera 5 is sent to the image processing apparatus 7. The imageprocessing apparatus 7 converts the image data picked up by theultraviolet CCD camera 5 into luminance value data and stores the data.After curing of the ultraviolet curable resin is completed, theapparatus 7 processes the stored luminance value data, quantifies theprocessed data so as to display a change of cured states of theultraviolet curable resin and displays the data on as a screen image.

Then, a method is described in detail, which quantifies cured states ofan ultraviolet curable resin from a change of luminance values in eachcured state captured by the image processing apparatus 7 and displaysthe result. It is assumed that the image luminance value at start ofcuring, that is, at a reaction rate of 0% is 0 and the image luminancevalue at completion of curing, that is, at a reaction rate of 100% is256. It is assumed that a change of image luminance values at this timeis changed proportionally to a measured luminance value. The imageluminance value at each position of the ultraviolet curable resin isobtained from the image luminance value and displayed at 256 gradations.

FIGS. 2A to 2D are screen images when obtaining a change of luminancevalues following curing of a general epoxy ultraviolet curable resinfrom the CCD camera 5. In the case of the ultraviolet light obtained bythe CCD camera 5, only a wavelength of 350 nm at which curing of theepoxy ultraviolet curable resin progresses at the highest speed isselected by the band-pass filter 3. FIG. 2A shows the luminance value 0of an ultraviolet curable resin before starting curing as an image. FIG.2B shows the luminance value of the ultraviolet curable resin after 100sec since starting curing as an image. FIG. 2C shows the luminance valueof the ultraviolet curable resin after 200 sec since starting curing asan image. FIG. 2D shows the luminance value of the ultraviolet curableresin after 300 sec since starting curing as an image. As shown in FIGS.2A to 2D, it is found that the image luminance value of the ultravioletcurable resin gradually lowers as passage of time and the curingreaction progresses.

This embodiment makes it possible to measure the cured state of anultraviolet curable resin in accordance with irradiation of not infraredlight or visible light which generates heat but ultraviolet light.Moreover, it is possible to capture a change of cured states of anultraviolet curable resin as a screen image and display the change ofthe cured states following passage of time.

Embodiment 2

The ultraviolet-curable-resin cured-state measuring method shown in theembodiment 1 can display a change of cured states of an ultravioletcurable resin as a screen image. As a result that the present inventorsfurther progress study, the inventors pinpoint that a more clear screenimage can be displayed by showing a temporal change of cured states ofan ultraviolet curable resin in terms of a change rate of theabsorbances obtained from the spectral characteristic of the lightreflected from the ultraviolet curable resin.

In this case, the relation between the change rate of the absorbancesfrom which a spectral characteristic can be obtained when applyingultraviolet light to an ultraviolet curable resin and the reaction rateobtained from an infrared spectrum change measured by the FT-IRdisclosed in Japanese Patent Application Laid-Open No. H06-294734 isdescribed below. The reaction rate of an ultraviolet curable resinobtained from an infrared spectrum change is known as a value for veryclearly showing a cured state. In this case, the ultraviolet curableresin containing an acrylic monomer (trade name GRANDIC RC C001 made byDAINIPPON INK AND CHEMICALS, INC.) (hereafter referred to as C001) isused as an example and a change rate of the absorbances in theultraviolet radiation region and a reaction rate obtained from aninfrared spectral change are compared and described below.

FIG. 3 shows a state of absorbance changes at the light wavelength ofthe ultraviolet curable resin C001 measured by an ultravioletspectroscope. Moreover, FIG. 3 shows absorbance changes followingpassage of time at this time at 0 sec, 100 sec, 200 sec, 300 sec and 600sec from start of curing. From FIG. 3, it is found that the ultravioletcurable resin C001 is almost transparent in a visible light region at awavelength of 380 nm or more and an absorbance change following curingis not seen but absorbances are changed in an ultraviolet wavelengthband at wavelength of 250 to 380 nm. Moreover, it is found that theresin C001 is a resin in which the absorbance remarkably increases at anultraviolet wavelength of approx. 300 nm as a curing reactionprogresses.

FIG. 4 shows a temporal change of absorbances at a wavelength of 300 nmof the ultraviolet curable resin C001 shown in FIG. 3. It is found thatthe absorbance exponentially increases simultaneously with start ofcuring and then it becomes almost constant after it reaches the maximumvalue for approx. 500 sec. In this case, the absorbance differencebetween the time before curing and the time of completion of curing is0.15 and this value is a large enough value for measuring an image.

When showing a change rate of absorbances following the passage of time,obtained from the absorbances shown in FIG. 4, as a reaction rate whenassuming the time of start of curing as 0% and the time of completion ofcuring as 100%, the line 1 (reaction rate 1) shown by a continuous linein FIG. 5 is obtained. Moreover, when measuring the infrared spectrum ofthe ultraviolet curable resin C001 by FT-IR, the reaction rate isobtained as the line 2 (reaction rate 2) shown by a dotted line in FIG.5. The reaction rate 2 can be obtained by the following (Expression 1)and (Expression 2).X={(Absorbance 1/Absorbance 2)/(Absorbance 3/Absorbance4)}×100  (Expression 1)

-   -   X: Remaining rate of double bonds of carbon        Reaction rate (%)=100−X  (Expression 2)

In this case, because the molecular structure of the ultraviolet curableresin C001 has double bonds of carbon, the ultraviolet curable resinC001 has the absorption peak at a wavelength of 810 cm⁻¹ (12.3 μm). Theabsorbance 1 is an absorbance at a wavelength of 12.3 μm at a certaintime after progress of curing is started and the absorbance 3 is anabsorbance at a wavelength of 12.3 μm before start of curing.

Moreover, because the ultraviolet curable resin C001 has a benzene ringin its molecular structure, it also has the absorption peak at awavelength of 756 cm⁻¹ (13.2 μm). The absorbance 2 is an absorbance atthe wavelength of 13.2 μm at a certain time after progress of curing isstarted and the absorbance 4 is an absorbance at a wavelength of 13.2 μmbefore curing is started.

The ultraviolet curable resin C001 is polymerized because double bondsof carbon are ring-opened as curing progresses. As the value of theabsorbance 1 gradually decreases as curing progresses. However, even ifcuring progresses, the value of the absorbance 2 is not changed becausethe structure of the benzene ring is not influenced. Therefore, as shownin Expression 1, as a result of tracing the temporal change afterirradiation of ultraviolet light of the ratio between the absorbances 1and 2 of the ultraviolet curable resin C001 and the ratio between theabsorbances 3 and 4 of the resin C001 before starting curing, thecarbon-double-bond remaining rate (X) showing how many carbon doublebonds are decreased due to curing is known. The reaction rate of theultraviolet curable resin C001 can be obtained from the value of Xobtained through Expression 1 by Expression 2.

In FIG. 5, the reaction rate of the line 1 coincides with that of theline 2 very well. Therefore, the reaction rate 2 obtained frommeasurement of an infrared spectrum can be replaced with the change rate1 obtained from the absorbance measured by a ultraviolet spectroscopeusing ultraviolet light. That is, the cured state of an ultravioletcurable resin can be accurately obtained in such a manner that the curedstate of the ultraviolet curable resin measured by irradiation ofultraviolet light is quantified to a value equivalent to the reactionrate of an infrared spectrum known as a value very clearly showing acured state.

FIG. 6 is a schematic view showing a reaction-curable-resin cured-statemeasuring apparatus used in the embodiment 2 of the present invention.In this case, an ultraviolet curable resin is used as a reaction curableresin. This embodiment quantifies the cured state of the ultravioletcurable resin by a change rate of absorbances obtained from a change ofspectral characteristics and displays the quantified cured state byirradiating the ultraviolet light to the ultraviolet curable resin andmeasuring the reflected light. A member same as that of the embodiment 1is provided with the same symbol.

In FIG. 6, reference numeral 9 denotes an object to be measured(measuring object) made of an ultraviolet curable resin. Referencenumeral 1 denotes an ultraviolet light source. Reference numerals 2 aand 2 b denote half mirrors for branching the ultraviolet light emittedfrom the light source 1 in two directions. Reference numeral 3 denotes aband-pass filter for passing only a specific wavelength component ofultraviolet light. Reference numeral 4 denotes an ultraviolet lenscapable of condensing ultraviolet light and 5 denotes an ultraviolet CCDcamera for picking up the ultraviolet light reflected from a measuringobject condensed by the ultraviolet lens 4 as screen image data.Reference numeral 6 denotes a compact ultraviolet spectroscope formeasuring the wavelength and intensity (spectral characteristic) at acertain one point of the ultraviolet light reflected from a measuringobject. The compact ultraviolet spectroscope cannot capture the lightreflected from the measuring object as a screen image or it can measureonly the wavelength and intensity (spectral characteristic) at a certainone point. Reference numeral 7 denotes an image processing apparatus forconverting the luminance value of a measuring object made of anultraviolet curable resin into a cured state and displays the curedstate. The image processing apparatus 7 quantifies the cured state ofthe measuring object 9 from the change of luminance values obtained fromthe ultraviolet CCD camera 5 and the spectral characteristic obtainedfrom the compact ultraviolet spectroscope 6 and displays the curedstate. Reference numeral 8 denotes a stray light removal plate forshielding unnecessary ultraviolet light.

In the case of each of acrylic resins and epoxy resins widely used asultraviolet curable resins, the luminance value of reflected ultravioletlight is changed due to the curing reaction of each ultraviolet curableresin in the ultraviolet wavelength band as described above. In thiscase, it is known that at the time the ultraviolet curable resin changesits resin structure to a chemical structure for absorbing ultravioletwavelength light. That is, when the molecular structure of theultraviolet curable resin changes, the spectral characteristic of theultraviolet curable resin also changes. The embodiment quantifies thecured state of an ultraviolet curable resin from a screen image pickedup by the CCD camera 5 and taken in to the image processing apparatus 7and a value picked up by the compact ultraviolet spectroscope 6 anddisplays the quantified cured state.

First, the ultraviolet light (wavelengths of 250 to 380 nm) emitted fromthe ultraviolet light source 1 is divided into two directions of directadvance and reflection by the half mirror 2 a. The direct-advanceultraviolet light is shielded by the stray light removal plate 8. Theultraviolet light reflected from the half mirror 2 a is applied to anultraviolet curable resin serving as an object to be measured. Thecuring reaction of the ultraviolet curable resin is gradually progressedby ultraviolet light. The ultraviolet light reflected from theultraviolet curable resin passes through the half mirror 2 a and isdivided into two directions of direct advance and reflection again bythe half mirror 2 b. Only a specific wavelength component is extractedfrom the ultraviolet light passing through the half mirror 2 b by aband-pass filter 3 and picked up as a screen image by the ultravioletCCD camera 5. The image picked up by the ultraviolet CCD camera 5 issent to the image processing apparatus 7. Moreover, the intensityinformation of the ultraviolet light reflected from the half mirror 2 bis measured by the compact ultraviolet spectroscope 6 and the measuredvalue is sent to the image processing apparatus 7. The image processingapparatus 7 converts the image picked up by the ultraviolet CCD camera 5into luminance value data and stores the data. Moreover, the apparatus 7converts the value picked up by the compact ultraviolet spectroscope 6into absorbance data and stores the data. After curing of theultraviolet curable resin is completed, the apparatus 7 quantifies achange of cured states of the ultraviolet curable resin by comparing andcombining the stored luminance value data and absorbance data anddisplays the change.

Then, a method for quantifying the cured state of an ultraviolet curableresin from the screen image data picked up by the CCD camera 5 and takenin by the image processing apparatus 7 and the value picked up by thecompact ultraviolet spectroscope 6 is described below.

First, the screen image picked up by the CCD camera 5 is the same asthat of the embodiment 1. The luminance value in each cured state issuccessively stored in the image processing apparatus 7 in accordancewith progress of curing reaction. At the same time, the spectralcharacteristic at a desired point of the ultraviolet curable resin ismeasured by the compact ultraviolet spectroscope 6 to obtain theabsorbance. The value of the absorbance in each cured state is alsosuccessively stored in accordance with the progress of a curingreaction. The ultraviolet light emitted from the ultraviolet lightsource 1 is ultraviolet light having a broad intensity at wavelengths of250 to 380 nm as shown in FIG. 7. The absorbance (α) in this case can beobtained from the following expression (3).Absorbance (α)=−log(I/I ₀)  (Expression 3)

-   -   I: Intensity of UV light passing through a cured sample; and    -   I₀: Intensity of UV light entering the sample.

As a curing reaction progresses, the intensity I of the light passingthrough an ultraviolet curable resin gradually decreases compared to theintensity I₀ of the light entering the sample. Therefore, the absorbance(α) gradually increases as the curing reaction progresses. Incidentally,the intensity I₀ of the light entering the sample is assumed to be aconstant value. In this case, the absorbance (α) of the ultravioletcurable resin being cured is stored until curing of the ultravioletcurable resin is completed while relating it with the luminance valuepicked up by the CCD camera 5.

Then, after curing of the ultraviolet curable resin is completed, theluminance value picked up by the CCD camera 5 and the absorbanceobtained from the compact ultraviolet spectroscope 6 arearithmetic-processed. First, the luminance value in each cured state ofthe ultraviolet curable resin as picked up by the CCD camera 5 isconverted into the absorbance obtained from the compact ultravioletspectroscope 6. Then, the change rate of the absorbances at eachposition of the ultraviolet curable resin is obtained by assuming theluminance value at start of curing, that is, at a reaction rate of 0% as0 and the luminance value at completion of curing, that is, at areaction rate of 100% as 256 to display the change rate in 256gradations.

Then, a method for quantifying the cured state of an ultraviolet curableresin from a change of luminance values in each cured state captured bythe image processing apparatus 7 and display the cured state isdescribed below in detail. FIGS. 8A to 8D show image luminance values ofan epoxy ultraviolet curable resin of the embodiment 1 shown in FIG. 2as replaced with change rates of absorbances. FIG. 8A shows the changerate of the surface of an ultraviolet curable resin before curing isstarted, as an image. FIG. 8B shows the change rate of the ultravioletcurable resin after 100 sec since starting curing, as an image. FIG. 8Cshows the change rate of ultraviolet curable resin after 200 sec sincestarting curing, as an image. FIG. 8D shows the change rate of theultraviolet curable resin after 300 sec since starting curing, as animage. From FIGS. 8A to 8D, it is found that in the case of theultraviolet curable resin, the curing reaction successively progressesas the passage of time.

Moreover, the change of cured states of the ultraviolet curable resin asshown in FIGS. 8A to 8D can more clearly show the change compared to thechange of cured states of the ultraviolet curable resin of theembodiment 1 as shown in FIG. 2. That is, according to this embodiment,it is possible to more accurately measure the cured state of anultraviolet curable resin by applying ultraviolet light. Moreover, it ispossible to capture a change of cured states of an ultraviolet curableresin as a clearer screen image and more accurately display a change ofthe cured states following the passage of time.

Furthermore, in the case of this embodiment, a luminance value picked upby the CCD camera 5 and a spectral characteristic measured by thecompact ultraviolet spectroscope 6 are stored until curing of anultraviolet curable resin is completed and then, an arithmeticaloperation of these values is performed. However, the present inventionmakes it possible to perform an arithmetical operation simultaneouslywith measurement of an ultraviolet curable resin and display a curedstate in real time by previously measuring spectral characteristics ofthe ultraviolet curable resin before a curing reaction and aftercompletion of the curing reaction.

Embodiment 3

FIG. 9 is a schematic view showing a reaction-curable-resin cured-statemeasuring apparatus used in embodiment 3 of the present invention. Asshown in FIG. 9, by continuously arranging a plurality of dichroicmirrors, it is possible to measure rays of a plurality of wavelengths atthe same time.

In FIG. 9, reference numeral 1 denotes an ultraviolet light source and 9denotes an object to be measured made of an ultraviolet curable resin.Reference numerals 12 a, 12 b and 12 c denote dichroic mirrors forreflecting only a certain wavelength and passing rays of otherwavelengths and 13 a, 13 b and 13 c denote band-pass filters. Referencenumerals 14 a and 14 b denote ultraviolet lenses and 15 a and 15 bdenote ultraviolet CCD cameras. Reference numeral 14 denotes a visiblelight lens and 15 denotes a visible-light CCD camera. According to thisembodiment, it is also possible to carry out measurement at wavelengthsincluding not only ultraviolet light but also visible light region byusing the spectral characteristic of any one of the dichroic mirrors 12a, 12 b and 12 c corresponding to a wavelength to be measured.

For example, it is also possible to measure ultraviolet light of 300 nmby the dichroic mirror 12 a, band-pass filter 13 a, ultraviolet lens 14a and ultraviolet CCD camera 15 a, ultraviolet light of 350 nm by thedichroic mirror 12 b, band-pass filter 13 b, ultraviolet lens 14 b andultraviolet CCD camera 15 b and visible light of 500 nm by the dichroicmirror 12 c, band-pass filter 13, visible light lens 14 and visiblelight CCD camera 15.

Embodiment 4

FIG. 10 is a schematic view showing a reaction-curable-resin cured-statemeasuring apparatus of embodiment 4 of the present invention. In thecase of this embodiment, a diffraction grating 16 is set in which lightof a specific wavelength is reflected in a specific direction. Bycapturing the light reflected from the diffraction grating 16 by aplurality of optical systems respectively constituted of an ultravioletlens and an ultraviolet CCD corresponding to each wavelength, it ispossible to measure rays of a plurality of wavelengths at the same time.

In FIG. 10, reference numeral 1 denotes an ultraviolet light source and9 denotes an object to be measured made of an ultraviolet curable resin.Reference numeral 12 denotes a dichroic mirror for reflecting only acertain wavelength and passing rays of other wavelengths and 17 denotesa reflection mirror. Reference numerals 13 a, 13 b and 13 c denoteband-pass filters. Reference numerals 14 a and 14 b denote ultravioletlenses and 15 a and 15 b denote ultraviolet CCD cameras. Referencenumeral 14 denotes a visible light lens and 15 denotes a visible-lightCCD camera. Reference numeral 16 denotes a diffraction grating capableof performing measurement at not only ultraviolet light but alsowavelengths including up to a visible light region by using a gratingcapable of diffracting the light of a wavelength to be measured. Thatis, by using the spectral characteristic of any one of the dichroicmirrors 12 a, 12 b and 12 c corresponding to a wavelength to bemeasured, it is possible to perform measurement at not only ultravioletlight but also wavelengths including up to a visible light region.

For example, it is also possible to measure the ultraviolet light of 300nm by the diffraction grating 16, band-pass filter 13 a, ultravioletlens 14 a and ultraviolet CCD camera 15 a, the ultraviolet light of 350nm by the diffraction grating 16, band-pass filter 13 b, ultravioletlens 14 b and ultraviolet CCD camera 15 b and the visible light of 500nm by the diffraction grating 16, band-pass filter 13, visible lightlens 14 and visible-light CCD camera 15.

Embodiment 5

FIG. 11 is a sectional view showing the state in which a diffractionoptical device serving as an object to be measured in embodiment 5 ofthe present invention is held between a molding die and a base material.In FIG. 11, reference numeral 18 denotes an ultraviolet curable resinC001 to be cured by ultraviolet light. Reference numeral 19 denotes aglass base material serving as a diffraction optical device by beingjoined with the ultraviolet curable resin 18. Reference numeral 20denotes a molding die for forming the shape of the ultraviolet curableresin 18 and a minute shape 21 for transferring the shape to thediffraction optical device is formed on the surface of the molding die.

FIG. 12 is a schematic view showing a reaction-curable-resin cured-statemeasuring apparatus. The configuration of the measuring apparatus inFIG. 12 is principally equal to the configuration of the measuringapparatus in FIG. 6 but its arrangement is different. In FIG. 12,reference numeral 22 denotes an object to be measured (measuring object)in which the ultraviolet curable resin 18 is held between the glass basematerial 19 and the molding die 20 as shown in FIG. 11. Referencenumeral 23 denotes a ultraviolet light source. Reference numeral 24 adenotes a half mirror for branching the ultraviolet light emitted fromthe light source 1 in two directions. Reference numeral 25 denotes aband-pass filter for passing only a specific wavelength component ofultraviolet light. Reference numeral 26 denotes an ultraviolet lenscapable of condensing ultraviolet light. Reference numeral 27 denotes anultraviolet CCD camera for picking up, as a screen image, theultraviolet light reflected from a measuring object and condensed by theultraviolet lens 26. Reference numeral 24 b denotes a half mirror forbranching the ultraviolet light passing through the ultraviolet lens 4in two directions. Reference numeral 28 denotes a compact ultravioletspectroscope for measuring the wavelength and intensity (spectralcharacteristic) of the ultraviolet light branched by the half mirror 24b. Reference numeral 29 denotes an image processing apparatus forconverting the luminance value of a measuring object made of anultraviolet curable resin into a cured state and displaying the curedstate. Reference numeral 30 denotes a stray light removal plate forshielding unnecessary ultraviolet light.

The ultraviolet light (wavelengths of 250 to 380 nm) emitted from theultraviolet light source 23 is divided into two directions of directadvance and reflection by the half mirror 24 a. The half mirror 24 areflects the light having wavelengths of 250 to 380 nm by 50% and passesthe light by 50%. The direct-advance ultraviolet light is shielded bythe stray light removal plate 30. The ultraviolet light reflected fromthe half mirror 24 a is irradiated to the ultraviolet curable resin 18serving as a measuring object. The curing reaction of the ultravioletcurable resin 18 is gradually progressed by the ultraviolet light. Theabsorbance of the ultraviolet curable resin 18 is changed at theabove-described ultraviolet wavelength band in accordance with thecuring reaction. The ultraviolet light passing through the ultravioletcurable resin 18 and reflected from the surface of the molding die 20 isthen reflected by the half mirror 24 a and only the ultraviolet lighthaving a wavelength of 300 nm passes through the ultraviolet lens 26 bythe band-pass filter 25 having a transmission peak wavelength of 300 nmand a half-width of 5 nm. The ultraviolet light passing through theultraviolet lens 26 is branched in two directions of direct advance andreflection again by the half mirror 24 b. Only the specific wavelengthcomponent is extracted from the ultraviolet light passing through thehalf mirror 24 b by the band-pass filter 25 and picked up by theultraviolet CCD camera 27. The image picked up by the ultraviolet CCDcamera 27 is sent to the image processing apparatus 29.

Then, a measuring method making use of an ultraviolet-curable-resincured-state measuring apparatus is described below by referring to FIGS.13A to 13E. FIG. 13A is a schematic sectional view of a portion nearbyan outer periphery of a molding die for molding a diffraction grating. Astep of molding a minute-shape diffraction optical device by using themolding die is described below. In FIG. 13A, a ultraviolet curable resin18 a whose absorbance greatly changes at an ultraviolet wavelength of350 nm is dripped onto the center of a molding die 20 held by amolded-item support 31 in a quantity controlled by a dispenser 34. Aminute shape 21 is formed on the surface of the molding die 20.

Then, FIG. 13B shows a state in which a very small quantity of theultraviolet curable resin 18 a is dripped on the center of the surfaceof the minute shape 21.

Then, in the step shown in FIG. 13C, a very small quantity of anultraviolet curable resin 18 b same as the ultraviolet curable resin 18a is dripped onto the center of a glass base material 19 serving as thesubstrate of a molded item to first bring the ultraviolet curable resin18 a on the glass base material 19 into contact with the ultravioletcurable resin 18 b on the minute shape 21. Then, the glass base material19 is slowly lowered and fixed at a desired film-thickness position. Theultraviolet curable resin 18 a and ultraviolet curable resin 18 b(hereafter referred to as ultraviolet curable resin 18) are spread bymeans of the glass base material 19 and become a diffraction opticaldevice filling a space surrounded by the minute shape 21 and the glassbase material 19.

Then, in the step shown in FIG. 13D, the ultraviolet curable resin 18 isonce cured provisionally and then permanently cured by applyingultraviolet light (arrow) from the glass base material 19 side. In thiscase, the cured state of the ultraviolet curable resin is evaluated byusing the cured-state measuring apparatus shown in FIG. 12. Theultraviolet light for measurement also serves as the ultraviolet lightused to cure the ultraviolet curable resin 18. At the time, it ispossible to capture the in-face information on the cured state of theresin by extracting the ultraviolet light reflected from a measuringobject by the band-pass filter 25 having a transmission peak wavelengthof 350 nm and a half-width of 5 nm and taking in the ultraviolet lightas an image by the ultraviolet CCD camera 27 and then transferring theimage to the image processing apparatus 29. In this case, the lightsource for curing the resin and the light source for measuringabsorbance are the same ultraviolet light source 23 and the ultravioletlight having the above spectrum shown in FIG. 7 in wavelengths of 250 to400 nm is emitted from the light source.

Then, in the step shown in FIG. 13E, the molded product is released fromthe die by raising the support 31 around the glass base material. Theabove steps are also executed for another die for forming a diffractiongrating. Thus, two types of diffraction lenses respectively having aconcave or convex shape at the circumference are completed.

According to this embodiment, by capturing a temporal change of thecured state of a resin following irradiation of ultraviolet light by thecured-state measuring apparatus shown in FIG. 12, it is possible toobtain the information on the dependency on a curing speed or curingtime of an ultraviolet curable resin. Therefore, it is possible todecide an optimum curing condition and realize accurate control of thecured state of an ultraviolet curable resin in the diffraction opticaldevice fabrication process. Moreover, because of using ultravioletlight, it is possible to measure the cured state through a lens.

Embodiment 6

FIG. 14 is a schematic view of a compact camera module used inembodiment 6 of the present invention, in which a reaction curable resinis used for the compact camera module. The resin used is an epoxyadhesive (trade name ADEKA OPTOMER made by ASAHI DENKA KOGYO K.K.). Whenthe resin is cured by irradiating ultraviolet light from the glass faceside, the cured state of the resin is monitored by the cured-statemeasuring apparatus shown in FIG. 6 which is used in the embodiment 2.In FIG. 14, reference numeral 38 denotes a glass base material, 39denotes an adhesive, 40 denotes a spacer, 41 denotes a Fresnel plate and42 denotes a sealing material.

Embodiment 7

FIG. 15 is embodiment 7 of the present invention, in which a resincured-state measuring method is used to measure the cured state of theresin in the annealing step of a DOE replica forming process. In FIG.15, members same as those in FIG. 12 are provided with the samereference numerals and their description is omitted. Reference numeral43 denotes a high temperature furnace, 44 denotes a window member formonitoring the inside of a furnace and 45 denotes an ultraviolet curableresin serving as an object to be measured.

By using the above-described ultraviolet curable resin C001, thecured-state measurement shown in the embodiment 2 is executed to measurea change of cured states in the annealing step of a resin cured byultraviolet light. In the annealing step, the ultraviolet curable resin45 is put in the high temperature furnace 43 set to a temperature of 60to 80° C. to heat it for 0 to 24 hours. The curing reaction of theultraviolet curable resin 45 is measured in annealing. When C001 used asthe ultraviolet curable resin 45 is annealed for 20 hours at 60° C. and80° C., absorbances are changed as shown in FIG. 16. By capturing achange of absorbances of the ultraviolet curable resin 45 in the hightemperature furnace 43 by a cured-state measuring apparatus andmonitoring a cured state through a window member 44 for monitoring theinside of a furnace, it is possible to control curing conditions such asannealing temperature and annealing time and improve the yield.

In the case of the present invention, it is easy to select an opticalsystem such as a lens or mirror by using the ultraviolet light havingwavelengths of 250 to 380 nm as measurement light. Moreover, even in athermal environment such as a furnace, the ultraviolet light is veryuseful because it is possible to separate material information from heatinformation.

Moreover, an ultraviolet light source has an intensity not only for theultraviolet light having a wavelength of 250 to 380 nm but also for avisible light region. Therefore, by measuring an image in a visiblelight region at the same time, it is possible to capture an appearance(quality) inspection and a cured state (performance) at the same time.

Furthermore, this method can be used not only for the replica formingprocess of a diffraction optical device but also for various steps suchas formation, bonding and sealing by an ultraviolet curable resin.

Furthermore, when irradiating measurement light to an object to bemeasured including a resin material and capturing the light passingthrough the resin by a CCD, it is possible to correspond to variousprocesses for curing a resin such as light irradiation or heating byusing the transmission type, incident-light type or reflection type asan illumination method.

A reaction-curable-resin cured-state measuring method of the presentinvention makes it possible to capture a change of cured states of areaction curable resin as a screen image and measure the change as atemporal change. Thereby, by confirming the cured state of a reactioncurable resin, it is possible to analyze factors for causing curingirregularity and uncured state at the time of curing and derive anoptimum curing condition. Therefore, it is possible to prevent defectiveappearance due to the fluctuation of the cured state of a reactioncurable resin and prevent a defective product due to chipping of aminute shape portion when an optical device is released from a die ordue to a remaining uncured portion caused by insufficient curing.

Moreover, because it is possible to measure a cured state by usingultraviolet light, it is possible to directly use a light source forcuring when curing an ultraviolet curable resin. Therefore, it ispossible to make a measuring apparatus compact and particularly realizea measuring apparatus suitable for measurement in various in-lineprocesses for UV curing printing and coating material curing. Moreover,it is possible to perform ultraviolet curing and cured-state measurementat the same time.

This application claims priority from Japanese Patent Application Nos.2003-430423 filed on Dec. 25, 2003 and 2004-334804 filed on Nov. 18,2004, which are hereby incorporated by reference herein.

1. A reaction-curable-resin cured-state measuring apparatus comprising:an ultraviolet light source for irradiating ultraviolet light to areaction curable resin serving as an object to be measured; detectionmeans for detecting reflected ultraviolet light or transmittedultraviolet light from the reaction curable resin as screen image datahaving a certain area; and image processing means forarithmetic-processing the screen image data detected by the detectionmeans and quantifying the progress state of a curing reaction of thereaction curable resin following the passage of time as screen image. 2.The reaction-curable-resin cured-state measuring apparatus according toclaim 1, wherein a band-pass filter for extracting only a light of aspecific wavelength of reflected ultraviolet light or transmittedultraviolet light is further set between the reaction curable resin andthe detection means.
 3. The reaction-curable-resin cured-state measuringapparatus according to claim 2, wherein a luminance value of thereflected ultraviolet light or transmitted ultraviolet light isdetected, and the light having a specific wavelength extracted from theband-pass filter has at least one wavelength of wavelengths of 250 to380 nm at which the maximum change of luminance values following curingof the reaction curable resin appears.
 4. The reaction-curable-resincured-state measuring apparatus according to claim 3, furthercomprising: display means for displaying the quantified screen image,wherein the display means displays the change rate corresponding to theluminance values by setting the change rate of the luminance values to0% before the curing reaction and to 100% after completion of the curingreaction and thereby changing colors at a plurality of gradations.
 5. Areaction-curable-resin cured-state measuring apparatus comprising: anultraviolet light source for irradiating ultraviolet light to a reactioncurable resin serving as an object to be measured; a half mirror forbranching the ultraviolet light reflected from or transmitted throughthe reaction curable resin in two directions; detection means fordetecting one-hand ultraviolet light branched by the half mirror asscreen image data having a certain area; an ultraviolet spectroscope fordetecting a spectral characteristic at one specific point of theother-hand ultraviolet light branched by the half mirror; and imageprocessing means for arithmetic-processing the screen image datadetected by the detection means and the spectral characteristic detectedby the ultraviolet spectroscope and quantifying the progress state of acuring reaction of the reaction curable resin following the passage oftime as a screen image.
 6. The reaction-curable-resin cured-statemeasuring apparatus according to claim 5, wherein a band-pass filter forextracting only a light having a specific wavelength of reflectedultraviolet light or transmitted ultraviolet light is further setbetween the reaction curable resin and the detection means.
 7. Thereaction-curable-resin cured-state measuring apparatus according toclaim 6, wherein the detection means detects a luminance value of thereflected ultraviolet light or transmitted ultraviolet light, and thelight having a specific wavelength extracted by the band-pass filter hasat least one wavelength of wavelengths of 250 to 380 nm at which themaximum change of luminance values following curing of the reactioncurable resin appears.
 8. The reaction-curable-resin cured-statemeasuring apparatus according to claim 7 further comprising: displaymeans for displaying the quantified screen image; wherein the imageprocessing means converts the luminance values into absorbances obtainedfrom the spectral characteristic and displays the change rate of theabsorbance by setting the change rate of the absorbance to 0% before thecuring reaction and to 100% after completion of the curing reaction andchanging colors at a plurality of gradations.
 9. Thereaction-curable-resin cured-state measuring apparatus according toclaim 5, wherein a plurality of the detection means are arranged, andthe detection means detect ultraviolet rays having different wavelengthsat which the reflected ultraviolet light or transmitted ultravioletlight is extracted by a plurality of band-pass filters.
 10. Thereaction-curable-resin cured-state measuring apparatus according toclaim 5, wherein a plurality of the detection means are arranged, andthe detection means detect ultraviolet rays having different wavelengthsat which the reflected ultraviolet light or transmitted ultravioletlight is extracted by a diffraction grating.
 11. Areaction-curable-resin cured-state measuring method comprising: a stepof irradiating ultraviolet light to a reaction curable resin serving asan object to be measured; a step of detecting the ultraviolet lightreflected from or transmitted through the reaction curable resin asscreen image data having a certain area; a step of arithmetic-processingthe detected screen image data; and a step of quantifying the progressstate of a curing reaction of the reaction curable resin following thepassage of time as a screen image.
 12. The reaction curable resincured-state measuring method according to claim 11, wherein the screenimage data is detected by extracting only the light having a specificwavelength of the reflected ultraviolet light or transmitted ultravioletlight.
 13. The reaction-curable-resin cured-state measuring methodaccording to claim 12, wherein the screen image data is the luminancevalue of the reflected or transmitted ultraviolet light at at least onewavelength of wavelengths of 250 to 380 nm and the wavelength is awavelength at which the maximum change of luminance values followingcuring of the reaction curable resin appears.
 14. Thereaction-curable-resin cured-state measuring method according to claim13, wherein the quantified screen image is displayed for the change ratecorresponding to the luminance values by setting the change rate of theluminance values to 0% before the curing reaction and to 100% aftercompletion of the curing reaction and changing colors at a plurality ofgradations.
 15. The reaction-curable-resin cured-state measuring methodaccording to claim 11, wherein the reaction curable resin is anultraviolet curable resin.
 16. The reaction-curable-resin cured-statemeasuring method according to claim 11, wherein the reaction curableresin is an ultraviolet curable resin for forming an optical device tobe formed through replica molding.
 17. A reaction-curable-resincured-state measuring method comprising: a step of irradiatingultraviolet light to a reaction curable resin serving as an object to bemeasured; a step of branching the ultraviolet light reflected from ortransmitted through the reaction curable resin in two directions; a stepof detecting one-hand branched ultraviolet light as screen image datahaving a certain area and detecting the spectral characteristic at onespecific point of the other-hand branched ultraviolet light; and a stepof arithmetic-processing the detected screen image data and spectralcharacteristic and quantifying the progress state of the curing reactionof the reaction curable resin following the passage of time as a screenimage.
 18. The reaction-curable-resin cured-state measuring methodaccording to claim 17, wherein the screen image data is detected byextracting only the light having a specific wavelength of the reflectedultraviolet light or transmitted ultraviolet light.
 19. Thereaction-curable-resin cured-state measuring method according to claim18, wherein the screen image data is the luminance value of thereflected or transmitted ultraviolet light at at least one wavelength ofwavelengths of 250 to 380 nm and a wavelength at which the maximumchange of luminance values following curing of the reaction curableresin appears.
 20. The reaction-curable-resin cured-state measuringmethod according to claim 19, wherein the quantified screen image isdisplayed for the change rate of the absorbances by converting theluminance values into absorbances obtained from the spectralcharacteristic, setting the change rate of the absorbances to 0% beforethe curing reaction and to 100% after completion of the curing reaction,and changing colors at a plurality of gradations.
 21. Thereaction-curable-resin cured-state measuring method according to claim17, wherein the reaction curable resin is an ultraviolet curable resin.22. The reaction-curable-resin cured-state measuring method according toclaim 17, wherein the reaction curable resin is an ultraviolet curableresin for forming an optical device to be formed through replicamolding.